In the field of heating and air conditioning, there are known problems causing discomfort to the occupants, inefficiencies in the system resulting in excessive operating costs in operating a building, and problems in the operation and control of the present systems.
For example, a central building control of temperature, air flow, humidity, and the like, or even individual rooms and workstations leaves many persons in the building or within a room or in the vicinity of a workstation uncomfortable or dissatisfied with the condition of their particular work environment. Different people have different metabolisms and therefore differing comfort needs. Also different locations in a building, or even in a single room or closer yet in the vicinity of a workstation, are not satisfactorily heated or cooled, that is air conditioned, giving rise to complaints about discomfort and illness, resulting in absenteeism, sickness and, of course, loss of productivity.
Further, conventional air conditioning systems generally require expensive duct work and installations, usually in floors or ceilings or both which cause unnecessary heating or cooling of unused space, particularly the spaces that surround the duct work and spaces above the head level of the occupants. For example, the upper four feet of space in a room having a twelve foot ceiling is an unoccupied space and the air in that space need not be be controlled. The above mentioned duct work also imposes a substantial energy demand for the movement of air through the ducts and additionally presents difficulties in cleaning the ducts.
Prior and known systems with fixed floor or wall mounted air outlet grilles limited the location of furniture and equipment in a manner which would block the flow of air. Such prior systems also created areas of complaints and discomfort caused by high or low air velocity and/or high or low temperature depending upon the location and the proximity of the air outlet grilles. Also, air conditioning outlet grilles and ducts frequently need to be moved to accommodate changes in air conditioning load or the rearrangement of the work space or the individual workstations in an open space office layout, for example.
In today's world of large office buildings, not only in height but also in the expanse of the floors, it has become a design objective to provide individual work spaces and individual workstations in generally wide open rooms. That is, instead of providing each occupant with his or her own permanent, generally enclosed room or office, a number of workstations or cubicles are provided with each having partitions or room dividers which partially enclose the space to create a separate work space, which partitions or dividers do not extend to the ceiling of the room. Often, these workstations include two, three or more partitions for the purpose of providing the worker with a feeling of privacy.
While such workstations may be economically beneficial with regard to the amount of floor space being used, the partitions create an impediment to flow of the conditioned air throughout the room. That is, conditioned air flows freely in the area above and around the workstations, but within the workstations or between the room dividers there is no means for providing the workstation occupant with an acceptable flow of conditioned air. Therefore, the workers often become uncomfortable, or even ill, which in turn decreases productivity and/or causes absenteeism.
Consequently, in the field of heating or cooling air, there exists a need for providing a flow of conditioned air directly to or near a person seated at a workstation as well as to occupants of the surrounding area. More particularly there exists a need for a workstation to be so equipped wherein the occupant can individually control and obtain the amount of conditioned air supplied within the workstation for maximizing the comfort, well being, health and level of productivity of each worker, while maintaining a desirable flow of conditioned air to the surrounding area.
Conventional room dividers for workstations may supply conditioned air to workstations, which conditioned air flows through an air flow grille at about the height where the workers is seated but the worker has very little control over the flow of the air or its direction. Such room dividers consist of a hollow space being created by panels spaced from each other by a predetermined distance to define an air flow there between. The hollow room divider or partition is placed on an opening in the floor which floor is spaced above the slab of the building floor to thereby form a large or major air plenum having conditioned air contained therein having a pressure at or near the atmospheric pressure. Applicants' prior Pat. Nos. 4,646,966; 4,860,642; 5,135,436; 5,238,452 are directed to this type of installation and to the control of the environment in an open office space. Applicants' present inventive concept is directed to an under the desk air terminal. There are other attempts in the prior art to bring conditioned air as close to a person or worker as is possible and to give this person or worker some semblance of control of the conditioned air.
U.S. Pat. No. 374,424 discloses a device for supplying fresh air to the environment of an auditorium and where the air blows directly to the chair of the occupant without any mechanical intervention.
U.S. Pat. No. 1,194,527 shows the ventilation of a class room wherein the outside air under pressure enters the class room through a ventilated floor panel and is further distributed into the desk where the pupil is sitting. The pupil may have some control over the amount of flow to or through the desk. In both of the previously cited patents the air flow is not conditioned or modified as to heat or cold.
U.S. Pat. No. 2,140,829 describes an air conditioning system wherein there is a cooling of high ceiling rooms by providing a stratum of cooled and dehumidified air in the lower levels of the room up to a height of the occupants without undertaking the relatively great cost and complication of treating all the air in the room.
U.S. Pat. No. 2,341,125 illustrates a way of ventilating a desk as a workstation by simply mounting a fan within a rear of the desk and by blowing air at the person and by given the person working at the desk somewhat of a control of the fan by positioning the same or by controlling the speed of the air flow.
U.S. Pat. No. 2,507,643 teaches the ventilation of restaurant equipment by supplying air to and from restaurant table and chair equipment. The person or persons seated at the equipment have no control over the flow and direction of the flow of air.
U.S. Pat. No. 2,572,120 shows a ventilated table having a fan mounted in a horizontal position which is emitting air in a horizontal direction and air flows out of he lateral sides of the table.
U.S. Pat. No. 2,616,617 illustrates a ventilated table similarly constructed as the table in the immediately cited patent above.
U.S. Pat. No. 2,734,990 discloses a desk as a workstation having a combination fan and heater mounted therein. The fan blows conditioned air (heat) directly at the person sitting at the desk. The direction of the air flow is adjustable by tilting the fan in one direction or the other and the level of heat is adjustable by way of a rheostat.
U.S. Pat. No. 2,835,186 discloses an air conditioning system wherein there are upstanding air emission columns receiving conditioned air through ducts in the floor of the system. It is considered to be a local or spot air conditioning system.
U.S. Pat. No. 2,877,990 discloses a novel building structure embodying a multi-cellular load supporting floor having a novel air distributing and electrical wiring system therein wherein both heated or cooled air and electrical wiring are distributed through selected ones of the cells of the floor
U.S. Pat. No. 3,322,055 teaches the elimination of duct work in a building by adding fan driven diffusers in the ceiling whereby the air chamber in the ceiling may be used as an unpressurized distribution chamber.
U.S. Pat. No. 3,516,347 shows the use of a double plenum air conditioning system creating a space between a structural slab and the floor or roof above of a building and the double plenum is divided by a horizontal partition into an upper and a lower plenum and to one of the plenums a supply air is fed and from the other of the plenums return air is withdrawn. The supply of air can be hot, cold or neutral. Inlets and outlets connect the plenums through the slab to the room below or through the floor to the room above.
U.S. Pat. No. 4,035,018 discloses a system whereby conditioned air is distributed through a floor plenum to a multiple of chairs having an exhaust contained in each one of the chairs to expel the conditioned air into the general environment of the room. The occupants of the chairs have no control over the speed and direction of the air flowing into the room.
U.S. Pat. No. 4,135,440 illustrates an air conditioning system having both ceiling and floor plenums and each of the plenums has individual air outlets diffusing into the room between the plenums. In addition there are individual elongated air outlet tubes suspended from the ceiling plenum or upstanding from the floor plenum. Each of the outlet tubes can be directed against a person sitting at a workstation. The respective person has control over the direction of the air emanating from the outlets.
U.S. Pat. No. 4,378,727 shows an open space office system including a plurality of freestanding workstations which are constructed of vertical panels and horizontal work surfaces. The room in which the workstations are arranged are provided with central ventilation means which provides air circulation within the room. Each workstation includes at least one common conduit arranged adjacent the work surface thereof. A vent disposed in each of the workstations communicates with the conduit thereby providing an air flow path from the central ventilation system through the room to the conduit.
U.S. Pat. No. 4,531,454 is directed to an air conditioning system in a building with floor tiles covering an under floor plenum of an air conditioning system. There are flexible ducts leading from an air conditioning unit. At the end of each flexible duct is a fan air terminal. Each of the fan units can discharge conditioned air from the floor into the general atmosphere of the room.
U.S. Pat. No. 4,775,001 discloses a zoned air conditioning system using a room air terminal which has the same horizontal dimensions as a floor tile of a raised tile floor such that the terminal may replace one tile in such a floor. The terminal includes a cool air inlet below the floor for drawing in cooling air circulated in the under floor space and a return air inlet in the top surface of the terminal. An upstanding air duct, taking air from underneath the floor plenum, may blow conditioned air against a person sitting at a workstation.
U.S. Pat. No. 4,872,397 illustrates a personal environmental module for controlling the environment of a workstation. The module includes a housing having an air inlet and a pair of air outlets with a pair of dampers mounted in the air inlet and one of the dampers is connected to a predetermined air source and the other damper is connected to room air. The above noted personal environmental module (PEM) enables each worker to control the air temperature, air flow, noise level, light level and radiant heat at the workstation.
U.S. Pat. No. 5,154,498 is directed to a portable desk apparatus including among other things a modification which includes a cooling housing selectively and removably mounted to an upper board member to direct cooling air to a user of the organization permitting its use in a convenient manner in various environments.
Another known air conditioned workstation is known under the word "Climadesk". It is described as a plenum which is installed under the top of a desk. The air plenum has an inlet to receive conditioned air from an air conditioning unit being placed apart but adjacent the desk. The air conditioning unit receives fresh air from the outside of the building through an air intake vent. The air plenum installed under the top surface of the desk directs the conditioned air toward a person sitting at the desk. The conditioned air is exiting toward the person by way of two front louvers and is further directed upwardly from the top surface of the desk in front of the person sitting at the desk. The temperature of the conditioned air can be controlled by way of a thermostat located on a front panel of the desk. This kind of an arrangement greatly reduces the mobility of such a workstation and thereby eliminates an effective arrangement of all of the workstations in an open office concept.
German published specification (Offenlegungsschrift) No. 24 07 448 discloses a workstation in the form of a desk receiving conditioning air by way of a flexible hose through the floor having air ducts therein. The occupant at the desk has no control over the flow of the air with regard to direction and/or speed.
German published specification (Offenlegungsschrift) No. 27 19 570 discloses a similar system as was disclosed in the German publication supra. In this arrangement conditioned air is supplied by way of ducts located below the floor of the open office area. From there the conditioned air is funneled by way of upstanding tubes located at each of the workstations. The conditioned air is blown into the room at a location above the desk surface at each of the workstations. The occupant at the desk has some control over the speed and direction of the air flowing through the outlets of the upstanding tubes.
German published specification (Offenlegungsschrift) No. 29 38 702 is similar to both German publications discussed above and does not add any more knowledge to the already known prior art.
Japanese Patent No. 61-11535 discloses an air conditioning system having a floor air plenum installed over a floor slab of a building. The conditioned air is driven by a fan into a hollow partition situated over an opening in the floor. Conditioned air may exit at a higher elevation than the height of a desk into the room. At the bottom of the floor whereupon the desk is located, there is a further air outlet which is directing conditioned air to the feet of a person sitting at the desk. It appears that said person has very little control over the amount, speed and direction over the conditioned air entering the vicinity of the desk.